Journal articles: 'Optic lobe'

1

Poeck, B., A. Hofbauer, and G. O. Pflugfelder. "Expression of the Drosophila optomotor-blind gene transcript in neuronal and glial cells of the developing nervous system." Development 117, no. 3 (March 1, 1993): 1017–29. http://dx.doi.org/10.1242/dev.117.3.1017.

Full text

Abstract:

Mutations in the complex gene locus optomotor-blind (omb) can lead to defects in the development of both the optic lobes and external features of the adult fly. We describe here the expression of omb in the developing and adult nervous system using in situ hybridization. During embryogenesis, omb expression is first observed in the optic lobe anlagen. It later expands to a larger part of the developing larval brain and to the gnathal lobes. Cells in the ventral and peripheral nervous systems begin to express omb after completion of germ band extension. Later in embryonic development, expression declines and only persists in the antennomaxillary complex and in part of the brain hemispheres. During the larval and pupal stages, omb expression in the brain is confined to the developing optic lobes and contiguous regions of the central brain. At these stages, only a few cells show expression in the ventral ganglion. In the eye imaginal disc, transcript accumulation is most conspicuous in a group of presumptive glia precursor cells posterior to the morphogenetic furrow and in the optic stalk. In the adult brain, expression is prominent in several regions of the optic lobe cortex and along the border between central brain and optic lobes. In the mutation In(1)ombH31, 40 kb of regulatory DNA, downstream from the transcription unit, are removed from the omb gene. In(1)ombH31 is characterized by the lack of a set of giant interneurons from the lobula plate of the adult optic lobes. We find that, already during embryogenesis, there is a drastic difference between wild type and In(1)ombH31 in the level of the omb transcript in the optic lobe primordia. The adult mutant phenotype may thus be caused by omb misexpression during embryonic development.

APA, Harvard, Vancouver, ISO, and other styles

2

Koushafar, Z., and A. Mohammadpour. "Morphological study of the midbrain tectum in ostrich (Struthio camelus) embryo." BULGARIAN JOURNAL OF VETERINARY MEDICINE 22, no. 2 (2019): 143–51. http://dx.doi.org/10.15547//bjvm.2064.

Full text

Abstract:

In this study the morphological features of the optic tectum in ostrich embryo were studied macroscopically and microscopically. After gross anatomical study, fixed specimens of the optic lobes in 30th, 36th and 40th embryonic days were processed for paraffin sections. Sections were stained by Harris haematoxylin and eosin (H&E), Luxol Fast Blue/Cresyl Echt Violet and Malory PTAH dyes. The optic lobes had large volumes even on the 30th embryonic day and increased proportionally to age. The optic lobe consisted of two parts: gray matter (outer) and white matter (inner). The first external layer of the optic lobe e.g. molecular layer consisted of neural fibres, neuroglia and scarce small neurons. The most common appearance of the optic lobes was characterised by small to medium-sized neurons (rounded to pyramid-shaped with large and pale nucleus consistong of obvious nucleoli arranged in three layers whose thickness increased in the deeper one) supported by neuroglia. Larger size neurons and occasionally multipolar neurons were presented in the interior compared with these layers. The lateral mesencephalic nucleus was detectable in the optic lobe base even on 30th embryonic day and was composed of few multipolar neurons supported by neuroglia. The tectal ventricles were lined with simple cuboidal ciliated ependymal cells in the embryonic period. As embryonic age increased, the ratio of tectal ventricle volume to its thickness decreased. Special stainings showed that Nissl bodies and myelin fibres, also glial fibres were available from the 30th embryonic day and that their density, especially myelin fibres density, increased with age.

APA, Harvard, Vancouver, ISO, and other styles

3

Saifullah, A. S. M., and Kenji Tomioka. "Serotonin sets the day state in the neurons that control coupling between the optic lobe circadian pacemakers in the cricketGryllus bimaculatus." Journal of Experimental Biology 205, no. 9 (May 1, 2002): 1305–14. http://dx.doi.org/10.1242/jeb.205.9.1305.

Full text

Abstract:

SUMMARYThe bilaterally paired optic lobe circadian pacemakers of the cricket Gryllus bimaculatus mutually exchange photic and circadian information to keep their activity synchronized. The information is mediated by a neural pathway, consisting of the so-called medulla bilateral neurons,connecting the medulla areas of the two optic lobes. We investigated the effects of serotonin on the neural activity in this coupling pathway. Spontaneous and light-induced electrical activity of the neurons in the coupling pathway showed daily variations, being more intense during the night than the day. Microinjection of serotonin or a serotonin-receptor agonist,quipazine, into the optic lobe caused a dose- and time-dependent inhibition of spontaneous and light-induced responses, mimicking the day state. The amount of suppression was greater and the recovery from the suppression occurred faster during the night. Application of metergoline, a non-selective serotonin-receptor antagonist, increased spontaneous activity and light-evoked responses during both the day and the night, with higher effect during the day. In addition, metergoline effectively attenuated the effects of serotonin. These facts suggest that in the cricket's optic lobe, serotonin is released during the daytime and sets the day state in the neurons regulating coupling between the bilaterally paired optic lobe circadian pacemakers.

APA, Harvard, Vancouver, ISO, and other styles

4

Tix, S., J. S. Minden, and G. M. Technau. "Pre-existing neuronal pathways in the developing optic lobes of Drosophila." Development 105, no. 4 (April 1, 1989): 739–46. http://dx.doi.org/10.1242/dev.105.4.739.

Full text

Abstract:

We have identified a set of larval neurones in the developing adult optic lobes of Drosophila by selectively labelling cells that have undergone only a few mitoses. A cluster of three cells is located in each of the optic lobes near the insertion site of the optic stalk. Their axons fasciculate with fibres of the larval optic nerve, the Bolwig's nerve, and then form part of the posterior optic tract. These cells are likely to be first order interneurones of the larval visual system. Unlike the Bolwig's nerve, they persist into the adult stage. The possibility of a pioneering function of the larval visual system during formation of the adult optic lobe neuropil is discussed.

APA, Harvard, Vancouver, ISO, and other styles

5

Wang, Hongxia, Richard B. Dewell, Markus U. Ehrengruber, Eran Segev, Jacob Reimer, Michael L. Roukes, and Fabrizio Gabbiani. "Optogenetic manipulation of medullary neurons in the locust optic lobe." Journal of Neurophysiology 120, no. 4 (October 1, 2018): 2049–58. http://dx.doi.org/10.1152/jn.00356.2018.

Full text

Abstract:

The locust is a widely used animal model for studying sensory processing and its relation to behavior. Due to the lack of genomic information, genetic tools to manipulate neural circuits in locusts are not yet available. We examined whether Semliki Forest virus is suitable to mediate exogenous gene expression in neurons of the locust optic lobe. We subcloned a channelrhodopsin variant and the yellow fluorescent protein Venus into a Semliki Forest virus vector and injected the virus into the optic lobe of locusts ( Schistocerca americana). Fluorescence was observed in all injected optic lobes. Most neurons that expressed the recombinant proteins were located in the first two neuropils of the optic lobe, the lamina and medulla. Extracellular recordings demonstrated that laser illumination increased the firing rate of medullary neurons expressing channelrhodopsin. The optogenetic activation of the medullary neurons also triggered excitatory postsynaptic potentials and firing of a postsynaptic, looming-sensitive neuron, the lobula giant movement detector. These results indicate that Semliki Forest virus is efficient at mediating transient exogenous gene expression and provides a tool to manipulate neural circuits in the locust nervous system and likely other insects.NEW & NOTEWORTHY Using Semliki Forest virus, we efficiently delivered channelrhodopsin into neurons of the locust optic lobe. We demonstrate that laser illumination increases the firing of the medullary neurons expressing channelrhodopsin and elicits excitatory postsynaptic potentials and spiking in an identified postsynaptic target neuron, the lobula giant movement detector neuron. This technique allows the manipulation of neuronal activity in locust neural circuits using optogenetics.

APA, Harvard, Vancouver, ISO, and other styles

6

Serikaku, M. A., and J. E. O'Tousa. "sine oculis is a homeobox gene required for Drosophila visual system development." Genetics 138, no. 4 (December 1, 1994): 1137–50. http://dx.doi.org/10.1093/genetics/138.4.1137.

Full text

Abstract:

Abstract The somda (sine oculis-medusa) mutant is the result of a P element insertion at position 43C on the second chromosome. somda causes aberrant development of the larval photoreceptor (Bolwig's) organ and the optic lobe primordium in the embryo. Later in development, adult photoreceptors fail to project axons into the optic ganglion. Consequently optic lobe development is aborted and photoreceptor cells show age-dependent retinal degeneration. The so gene was isolated and characterized. The gene encodes a homeodomain protein expressed in the optic lobe primordium and Bolwig's organ of embryos, in the developing adult visual system of larvae, and in photoreceptor cells and optic lobes of adults. In addition, the SO product is found at invagination sites during embryonic development: at the stomadeal invagination, the cephalic furrow, and at segmental boundaries. The mutant somda allele causes severe reduction of SO embryonic expression but maintains adult visual system expression. Ubiquitous expression of the SO gene product in 4-8-hr embryos rescues all somda mutant abnormalities, including the adult phenotypes. Thus, all deficits in adult visual system development and function results from failure to properly express the so gene during embryonic development. This analysis shows that the homeodomain containing SO gene product is involved in the specification of the larval and adult visual system development during embryogenesis.

APA, Harvard, Vancouver, ISO, and other styles

7

Liu, Yung-Chieh, Tsung-Han Liu, Chun-Chieh Yu, Chia-Hao Su, and Chuan-Chin Chiao. "Mismatch between the eye and the optic lobe in the giant squid." Royal Society Open Science 4, no. 7 (July 2017): 170289. http://dx.doi.org/10.1098/rsos.170289.

Full text

Abstract:

Giant squids ( Architeuthis ) are a legendary species among the cephalopods. They live in the deep sea and are well known for their enormous body and giant eyes. It has been suggested that their giant eyes are not adapted for the detection of either mates or prey at distance, but rather are best suited for monitoring very large predators, such as sperm whales, at distances exceeding 120 m and at a depth below 600 m (Nilsson et al. 2012 Curr. Biol. 22 , 683–688. ( doi:10.1016/j.cub.2012.02.031 )). However, it is not clear how the brain of giant squids processes visual information. In this study, the optic lobe of a giant squid ( Architeuthis dux , male, mantle length 89 cm), which was caught by local fishermen off the northeastern coast of Taiwan, was scanned using high-resolution magnetic resonance imaging in order to examine its internal structure. It was evident that the volume ratio of the optic lobe to the eye in the giant squid is much smaller than that in the oval squid ( Sepioteuthis lessoniana ) and the cuttlefish ( Sepia pharaonis ). Furthermore, the cell density in the cortex of the optic lobe is significantly higher in the giant squid than in oval squids and cuttlefish, with the relative thickness of the cortex being much larger in Architeuthis optic lobe than in cuttlefish. This indicates that the relative size of the medulla of the optic lobe in the giant squid is disproportionally smaller compared with these two cephalopod species. This morphological study of the giant squid brain, though limited only to the optic lobe, provides the first evidence to support that the optic lobe cortex, the visual information processing area in cephalopods, is well developed in the giant squid. In comparison, the optic lobe medulla, the visuomotor integration centre in cephalopods, is much less developed in the giant squid than other species. This finding suggests that, despite the giant eye and a full-fledged cortex within the optic lobe, the brain of giant squids has not evolved proportionally in terms of performing complex tasks compared with shallow-water cephalopod species.

APA, Harvard, Vancouver, ISO, and other styles

8

Elphick, M., L. Williams, and M. Shea. "New features of the locust optic lobe: evidence of a role for nitric oxide in insect vision." Journal of Experimental Biology 199, no. 11 (November 1, 1996): 2395–407. http://dx.doi.org/10.1242/jeb.199.11.2395.

Full text

Abstract:

The enzyme nitric oxide synthase can be localised by NADPH-diaphorase histochemistry. Here we have applied this technique to the optic lobe of the locust Schistocerca gregaria and revealed new features of the insect visual system. Extensive but locally intense staining is associated with identified tracts, distinct neuropiles and cell body groups, and a detailed analysis of stained elements is provided here. The most striking staining occurs in the anterior lobe of the lobula complex and its connection with the medulla by means of the dorsal uncrossed bundle. Eleven groups of cell bodies are identified and their contribution to fibre tracts and neuropile areas is described. Diaphorase-positive fibre tracts pass between all major subdivisions of the optic lobe, but there are no conspicuous fibre connections from the optic lobe to the brain. The widespread distribution of NADPH-diaphorase staining in the optic lobe suggests that nitric oxide is likely to play an important role in information processing in insect vision.

APA, Harvard, Vancouver, ISO, and other styles

9

Hussain, Raflaa S. H., and Amel A. Al-taee. "Comparative Study between Brain and Optic Lobe of Falcon (Falco Columbarius) and Owl (Bubo Bubo)." Pakistan Journal of Medical and Health Sciences 16, no. 4 (April 30, 2022): 909–12. http://dx.doi.org/10.53350/pjmhs22164909.

Full text

Abstract:

Background: In Iraq have been collected 10 Falcon (Falco columbarius) and 10 Owl (Bubo bubo ) to obtain their brain (optic lobe) and histological comparative between them. Method: In recent study have been collected specimens and used hematoxylin and eosin stain and used silver stain to compare between them. Result: Our result show weight of brain of falcon was less than owl (4.2± 0.04830 , 4.7± 0. 05164) respectively while weight of optic lobe of falcon was more than owl (1.2±0.05270 , 1.1± 0.05164) respectively. Optic lobe of falcon was consist of six layers with thickness (770.7 ±0.48305 ) while owl was consist of three layers only with (707.7±0.48305). Conclusion: brain weight of falcon is less than owl because of long distance which be fly and weight of optic lobe of falcon is more than owl because it has high vision more than owl

APA, Harvard, Vancouver, ISO, and other styles

10

Rodrigues, Eduardo Mello, Gustavo Rassier Isolan, Lia Grub Becker, Leandro Infantini Dini, Marco Antônio Schlindwein Vaz, and Thomas More Frigeri. "Anatomy of the optic radiations from the white matter fiber dissection perspective: A literature review applied to practical anatomical dissection." Surgical Neurology International 13 (July 22, 2022): 309. http://dx.doi.org/10.25259/sni_1157_2021.

Full text

Abstract:

Background: Knowledge of the anatomical course of the optic radiations and its relationship to medial temporal lobe structures is of great relevance in preoperative planning for surgery involving the temporal lobe to prevent damage that may result in postsurgical visual field deficits. Methods: In this anatomical study, we reviewed the literature on this topic and applied the information to practical anatomical dissection. The three-dimensional relationship between the course of the optic radiations and structures accessed in the main microneurosurgical approaches to the medial temporal lobe was examined by applying Klingler’s white matter fiber dissection technique to five formalin-fixed human brains. The dissections were performed with an operating microscope at magnifications of ×3–×40. High-resolution images were acquired during dissection for identification of the anatomical structures, focusing on the characterization of the course of the optic radiations in relation to medial temporal lobe structures. Results: In all five dissected brains, we could expose and clearly define the relationship between the optic radiations and medial temporal lobe structures, improving our understanding of these complex structures. Conclusion: The knowledge gained by studying these relationships will help neurosurgeons to develop risk-adjusted approaches to prevent damage to the optic radiations in the medial temporal region, which may result in a disabling visual field deficit.

APA, Harvard, Vancouver, ISO, and other styles

11

Bombardi, Cristiano, Giulia Salamanca, Claudio Tagliavia, Annamaria Grandis, Fanny Mille, Maria Grazia De Iorio, and Giulietta Minozzi. "Immunohistochemical Distribution of Serotonin Transporter (SERT) in the Optic Lobe of the Honeybee, Apis mellifera." Animals 12, no. 16 (August 10, 2022): 2032. http://dx.doi.org/10.3390/ani12162032.

Full text

Abstract:

Visual information is processed in the optic lobes, which consist of three retinotopic neuropils. These are the lamina, the medulla and the lobula. Biogenic amines play a crucial role in the control of insect responsiveness, and serotonin is clearly related to aggressiveness in invertebrates. Previous studies suggest that serotonin modulates aggression-related behaviours, possibly via alterations in optic lobe activity. The aim of this investigation was to immunohistochemically localize the distribution of serotonin transporter (SERT) in the optic lobe of moderate, docile and aggressive worker honeybees. SERT-immunoreactive fibres showed a wide distribution in the lamina, medulla and lobula; interestingly, the highest percentage of SERT immunoreactivity was observed across all the visual neuropils of the docile group. Although future research is needed to determine the relationship between the distribution of serotonin fibres in the honeybee brain and aggressive behaviours, our immunohistochemical study provides an anatomical basis supporting the role of serotonin in aggressive behaviour in the honeybee.

APA, Harvard, Vancouver, ISO, and other styles

12

Bausenwein, B., A. P. M. Dittrich, and K. F. Fischbach. "The optic lobe of Drosophila melanogaster." Cell & Tissue Research 267, no. 1 (January 1992): 17–28. http://dx.doi.org/10.1007/bf00318687.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Matsuo, Satoshi, Serhat Baydin, Abuzer Güngör, Erik H. Middlebrooks, Noritaka Komune, Koji Iihara, and Albert L. Rhoton. "Prevention of postoperative visual field defect after the occipital transtentorial approach: anatomical study." Journal of Neurosurgery 129, no. 1 (July 2018): 188–97. http://dx.doi.org/10.3171/2017.4.jns162805.

Full text

Abstract:

OBJECTIVEA postoperative visual field defect resulting from damage to the occipital lobe during surgery is a unique complication of the occipital transtentorial approach. Though the association between patient position and this complication is well investigated, preventing the complication remains a challenge. To define the area of the occipital lobe in which retraction is least harmful, the surface anatomy of the brain, course of the optic radiations, and microsurgical anatomy of the occipital transtentorial approach were examined.METHODSTwelve formalin-fixed cadaveric adult heads were examined with the aid of a surgical microscope and 0° and 45° endoscopes. The optic radiations were examined by fiber dissection and MR tractography techniques.RESULTSThe arterial and venous relationships of the lateral, medial, and inferior surfaces of the occipital lobe were defined anatomically. The full course of the optic radiations was displayed via both fiber dissection and MR tractography. Although the stems of the optic radiations as exposed by both techniques are similar, the terminations of the fibers are slightly different. The occipital transtentorial approach provides access for the removal of lesions involving the splenium, pineal gland, collicular plate, cerebellomesencephalic fissure, and anterosuperior part of the cerebellum. An angled endoscope can aid in exposing the superior medullary velum and superior cerebellar peduncles.CONCLUSIONSAnatomical findings suggest that retracting the inferior surface of the occipital lobe may avoid direct damage and perfusion deficiency around the calcarine cortex and optic radiations near their termination. An accurate understanding of the course of the optic radiations and vascular relationships around the occipital lobe and careful retraction of the inferior surface of the occipital lobe may reduce the incidence of postoperative visual field defect.

APA, Harvard, Vancouver, ISO, and other styles

14

Li, Wenmin, Yu Chen, Yan Liang, Yang Lu, and Zhou Meng. "Directivity Dependence of a Distributed Fiber Optic Hydrophone on Array Structure." Sensors 22, no. 16 (August 21, 2022): 6297. http://dx.doi.org/10.3390/s22166297.

Full text

Abstract:

A distributed fiber optic hydrophone (DFOH) is a new type of fiber optic hydrophone (FOH) with adjustable structure. The dependence of the directivity of a DFOH on array structure is theoretically and experimentally studied. The directivity function of a sensing channel and that of a DFOH are derived. Based on the directivity function, the simulations are performed. Finally, the theoretical analysis is demonstrated by the experiments performed on Qingyang lake, and the results reveal that the longer sensing channel length guarantees the lower first-order side lobe and the narrower main lobe. As the channel length increased from 1 to 3, the main lobe width and first-order side lobe height decreased by 4.9° and 6 dB, respectively. In addition, channel spacing is irrelevant to directivity as the spacing is shorter than the wavelength. As the channel spacing increased from 0 to 1, the variations of the main lobe width and first-order side lobe height are lower than 0.5° and 0.94 dB, respectively. This study would provide guidance for the structure design of a distributed fiber optic hydrophone in signal processing.

APA, Harvard, Vancouver, ISO, and other styles

15

Hayashi, Munehiro, Tomoki Kazawa, Hayato Tsunoda, and Ryohei Kanzaki. "The Understanding of ON-Edge Motion Detection Through the Simulation Based on the Connectome of Drosophila’s Optic Lobe." Journal of Robotics and Mechatronics 34, no. 4 (August 20, 2022): 795–807. http://dx.doi.org/10.20965/jrm.2022.p0795.

Full text

Abstract:

The optic lobe of the fly is one of the prominent model systems for the neural mechanism of the motion detection. How a fly who lives under various visual situations of the nature processes the information from at most a few thousands of ommatidia in their neural circuit for the detection of moving objects is not exactly clear though many computational models of the fly optic lobe as a moving objects detector were suggested. Here we attempted to elucidate the mechanisms of ON-edge motion detection by a simulation approach based on the TEM connectome of Drosophila. Our simulation model of the optic lobe with the NEURON simulator that covers the full scale of ommatidia, reproduced the characteristics of the receptor neurons, lamina monopolar neurons, and T4 cells in the lobula. The contribution of each neuron can be estimated by changing synaptic connection strengths in the simulation and measuring the response to the motion stimulus. Those show the paradelle pathway provide motion detection in the fly optic lobe has more robustness and is more sophisticated than a simple combination of HR and BL systems.

APA, Harvard, Vancouver, ISO, and other styles

16

Glavan, Gordana. "Histochemical Staining of Acetylcholinesterase in Carnolian Honeybee (Apis mellifera carnica) Brain after Chronic Exposure to Organophosphate Diazinon." Journal of Apicultural Science 64, no. 1 (July 2, 2020): 123–30. http://dx.doi.org/10.2478/jas-2020-0003.

Full text

Abstract:

AbstractOrganophosphate insecticides are known to inhibit the activity of enzyme acetylcholinesterase. They affect olfactory learning and memory formation in honeybees. These insecticides cause mushroom body inactivation in honeybees, but their influence on other brain regions involved in olfactory perception and memory is unknown. The goal of this study was to study the effects of organophosphate insecticide diazinon on carnolian honeybee (Apis mellifera carnica) acetylcholinesterase activity in the olfactory brain regions of antennal lobe, mushroom body and lateral procerebrum (lateral horn). The lamina, medulla and lobula of optic lobes were also analyzed. The level of acetylcholinesterase activity was visualized using the histochemical staining method. Densitometric analysis of histochemical signals indicated that diazinon inhibited acetylcholinesterase activity only in the lip of calyces of mushroom body, but not in other analyzed olfactory regions, antennal lobe and lateral procerebrum. The visual brain system optic lobes were also unaffected. This is in accordance with the literature reporting that mushroom body is the main brain center for olfactory learning and memory formation in honeybees.

APA, Harvard, Vancouver, ISO, and other styles

17

Olarotimi, Olumuyiwa Joseph, Imoleayo Sarah Oladeji, Olufemi Adesanya Adu, and Francis Ayodeji Gbore. "Acetylcholinesterase, Specific Acetylcholinesterase and Total Protein Concentrations in the Brain Regions of Broiler Chickens Fed Dietary Monosodium Glutamate." Turkish Journal of Agriculture - Food Science and Technology 7, no. 6 (June 25, 2019): 883. http://dx.doi.org/10.24925/turjaf.v7i6.883-887.2451.

Full text

Abstract:

The study was carried out to examine the effect of varied levels of dietary monosodium glutamate on acetylcholinesterase, specific acetylcholinesterase and total protein concentrations in the brain regions of broiler chickens. Three hundred (300) day – old unsexed Abor – acre chickens were randomly assigned to diets: A, B, C, D, E and F containing 0.00, 0.25, 0.50, 0.75, 1.00 and 1.25 g/kg MSG respectively. Each treatment was replicated 5 times with 10 birds per replicate. The birds were fed ad – libitum and provided with clean water for 8 weeks (56 days) after which 2 birds per replicates were slaughtered. The brains were removed, dissected into different regions comprising of the olfactory lobe, pineal body, optic lobe, cerebellum and the medulla oblongata. The different parts of the brain were homogenized to determine the acetylcholinesterase and total protein which were also used in the assessment of the specific acetylcholinesterase of the brain. No significant differences were observed in the acetylcholinesterase activity of the olfactory lobe, pineal body, optic lobe, cerebellum except for the medulla. Likewise, the dietary monosodium glutamate did not influence the activities of the total protein and specific acetylcholinesterase of the olfactory lobe portion of the brain. The dietary monosodium glutamate exerted significant effects on the total protein of other brain parts studied and which invariably resulted in significant changes in the specific acetylcholinesterase of the optic lobe, cerebellum and medulla except for the optic lobe. This study revealed that monosodium glutamate added to broilers diet above 0.75 g/kg significantly altered the concentration of the brain acetylcholinesterase, total protein and specific acetylcholinesterase thereby impaired brain functions.

APA, Harvard, Vancouver, ISO, and other styles

18

Shemesh, Ari, Laila Al-Shafai, Timo Krings, and Edward Margolin. "When the Problem Became the Solution." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 46, no. 6 (July 4, 2019): 767–69. http://dx.doi.org/10.1017/cjn.2019.239.

Full text

Abstract:

ABSTRACT:We present a unique case where a young man developed subtle cavernous sinus thrombosis (CST) due to underlying hypercoagulable state. He also had coexisting frontal lobe brain dural arteriovenous fistula (bdAVF). After CST developed, venous drainage from the optic nerve was redirected into the frontal lobe which was already under high venous pressure because of preexisting bdAVF. This caused backflow of venous blood into the optic nerve causing massive persistent optic nerve head swelling. Presumed acute venous hypertension event within bdAVF caused frontal mass effect presenting as seizure leading to thrombosis of bdAVF.

APA, Harvard, Vancouver, ISO, and other styles

19

Daniel, A., K. Dumstrei, J. A. Lengyel, and V. Hartenstein. "The control of cell fate in the embryonic visual system by atonal, tailless and EGFR signaling." Development 126, no. 13 (July 1, 1999): 2945–54. http://dx.doi.org/10.1242/dev.126.13.2945.

Full text

Abstract:

We describe here the role of the transcription factors encoding genes tailless (tll), atonal (ato), sine oculis (so), eyeless (ey) and eyes absent (eya), and EGFR signaling in establishing the Drosophila embryonic visual system. The embryonic visual system consists of the optic lobe primordium, which, during later larval life, develops into the prominent optic lobe neuropiles, and the larval photoreceptor (Bolwig's organ). Both structures derive from a neurectodermal placode in the embryonic head. Expression of tll is normally confined to the optic lobe primordium, whereas ato appears in a subset of Bolwig's organ cells that we call Bolwig's organ founders. Phenotypic analysis, using specific markers for Bolwig's organ and the optic lobe, of tll loss- and gain-of-function mutant embryos reveals that tll functions to drive cells to optic lobe as opposed to Bolwig's organ fate. Similar experiments indicate that ato has the opposite effect, namely driving cells to a Bolwig's organ fate. Since we can show that tll and ato do not regulate each other, we propose a model wherein tll expression restricts the ability of cells to respond to signaling arising from ato-expressing Bolwig's organ pioneers. Our data further suggest that the Bolwig's organ founder cells produce Spitz (the Drosophila TGFalpha homolog) signal, which is passed to the neighboring secondary Bolwig's organ cells where it activates the EGFR signaling cascade and maintains the fate of these secondary cells. The regulators of tll expression in the embryonic visual system remain elusive, as we were unable to find evidence for regulation by the ‘early eye genes’ so, eya and ey, or by EGFR signaling.

APA, Harvard, Vancouver, ISO, and other styles

20

Campos, A. R., K. F. Fischbach, and H. Steller. "Survival of photoreceptor neurons in the compound eye of Drosophila depends on connections with the optic ganglia." Development 114, no. 2 (February 1, 1992): 355–66. http://dx.doi.org/10.1242/dev.114.2.355.

Full text

Abstract:

The importance of retinal innervation for the normal development of the optic ganglia in Drosophila is well documented. However, little is known about retrograde effects of the optic lobe on the adult photoreceptor cells (R-cells). We addressed this question by examining the survival of R-cells in mutant flies where R-cells do not connect to the brain. Although imaginal R-cells develop normally in the absence of connections to the optic lobes, we find that their continued survival requires these connections. Genetic mosaic studies with the disconnected (disco) mutation demonstrate that survival of R-cells does not depend on the genotype of the eye, but is correlated with the presence of connections to the optic ganglia. These results suggest the existence of retrograde interactions in the Drosophila visual system reminiscent of trophic interactions found in vertebrates.

APA, Harvard, Vancouver, ISO, and other styles

21

Chen, Pei-Ju, Yan Li, and Chi-Hon Lee. "Dissection of the Head of a Live Fly for Functional Imaging." Cold Spring Harbor Protocols 2022, no. 7 (May 31, 2022): pdb.prot107889. http://dx.doi.org/10.1101/pdb.prot107889.

Full text

Abstract:

In this protocol, we outline procedures to mount the fly and to open up the head cuticle to expose the optic lobes for in vivo imaging. The fly is first inserted into a custom-made fly chamber in which the fly's head is stabilized on a piece of aluminum foil. Once the fly is mounted in the chamber, its head cuticle is removed, exposing the optic lobe for recording. The brain tissues (above the foil), including the optic lobes, should be bathed in fly saline. Meanwhile, the eyes (below the foil) are kept dry to receive light stimuli during the recording. A considerable level of expertise and hand dexterity is required to handle a small animal such as a fly, especially when opening its head capsule without damaging the brain tissue. This expertise should be gained through mindful repetition of the protocol. With appropriate preparation and skills, the success rate for this procedure can be >95%. Using this protocol, it is possible to record ultraviolet (UV)-sensing photoreceptors, which have long visual fibers that terminate at the medulla (the second optic neuropil). Depending on the visual neurons of interest, some modifications to fly mounting might be needed.

APA, Harvard, Vancouver, ISO, and other styles

22

Homberg, Uwe, Stanley Heinze, Keram Pfeiffer, Michiyo Kinoshita, and Basil el Jundi. "Central neural coding of sky polarization in insects." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1565 (March 12, 2011): 680–87. http://dx.doi.org/10.1098/rstb.2010.0199.

Full text

Abstract:

Many animals rely on a sun compass for spatial orientation and long-range navigation. In addition to the Sun, insects also exploit the polarization pattern and chromatic gradient of the sky for estimating navigational directions. Analysis of polarization–vision pathways in locusts and crickets has shed first light on brain areas involved in sky compass orientation. Detection of sky polarization relies on specialized photoreceptor cells in a small dorsal rim area of the compound eye. Brain areas involved in polarization processing include parts of the lamina, medulla and lobula of the optic lobe and, in the central brain, the anterior optic tubercle, the lateral accessory lobe and the central complex. In the optic lobe, polarization sensitivity and contrast are enhanced through convergence and opponency. In the anterior optic tubercle, polarized-light signals are integrated with information on the chromatic contrast of the sky. Tubercle neurons combine responses to the UV/green contrast and e-vector orientation of the sky and compensate for diurnal changes of the celestial polarization pattern associated with changes in solar elevation. In the central complex, a topographic representation of e-vector tunings underlies the columnar organization and suggests that this brain area serves as an internal compass coding for spatial directions.

APA, Harvard, Vancouver, ISO, and other styles

23

Sincoff, Eric H., Yunxi Tan, and Saleem I. Abdulrauf. "White matter fiber dissection of the optic radiations of the temporal lobe and implications for surgical approaches to the temporal horn." Journal of Neurosurgery 101, no. 5 (November 2004): 739–46. http://dx.doi.org/10.3171/jns.2004.101.5.0739.

Full text

Abstract:

Object. The aim of this anatomical study was to define more fully the three-dimensional (3D) relationships between the optic radiations and the temporal horn and superficial anatomy of the temporal lobe by using the Klingler white matter fiber dissection technique. These findings were correlated with established surgical trajectories to the temporal horn. Such surgical trajectories have implications for amygdalohippocampectomy and other procedures that involve entering the temporal horn for the resection of tumors or vascular lesions. Methods. Ten human cadaveric hemispheres were prepared with several cycles of freezing and thawing by using a modification of the method described by Klingler. Wooden spatulas were used to strip away the deeper layers of white matter progressively in a lateromedial direction, and various association, projection, and commissural fibers were demonstrated. As the dissection progressed, photographs of each progressive layer were obtained. Special attention was given to the optic radiation and to the sagittal stratum of which the optic radiation is a part. The trajectories of fibers in the optic radiation were specifically studied in relation to the lateral, medial, superior, and inferior walls of the temporal horn as well as to the superficial anatomy of the temporal lobe. In three of the hemispheres coronal sections were made so that the relationship between the optic radiation and the temporal horn could be studied more fully. In all 10 hemispheres that were dissected the following observations were made. 1) The optic radiation covered the entire lateral aspect of the temporal horn as it extends to the occipital horn. 2) The anterior tip of the temporal horn was covered by the anterior optic radiation along its lateral half. 3) The entire medial wall of the temporal horn was free from optic radiation fibers, except at the level at which these fibers arise from the lateral geniculate body to ascend over the roof of the temporal horn. 4) The superior wall of the temporal horn was covered by optic radiation fibers. 5) The entire inferior wall of the temporal horn was free from optic radiation fibers anterior to the level of the lateral geniculate body. Conclusions. Fiber dissections of the temporal lobe and horn demonstrated the complex 3D relationships between the optic radiations and the temporal horn and superficial anatomy of the temporal lobe. Based on the results of this study, the authors define two anatomical surgical trajectories to the temporal horn that would avoid the optic radiations. The first of these involves a transsylvian anterior medial approach and the second a pure inferior trajectory through a fusiform gyrus. Lateral approaches to the temporal horn through the superior and middle gyri, based on the authors' findings, would traverse the optic radiations.

APA, Harvard, Vancouver, ISO, and other styles

24

Strausfeld, Nicholas J., and Briana Olea-Rowe. "Convergent evolution of optic lobe neuropil in Pancrustacea." Arthropod Structure & Development 61 (March 2021): 101040. http://dx.doi.org/10.1016/j.asd.2021.101040.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Wentworth, S. L., and W. R. A. Muntz. "Development of the eye and optic lobe ofOctopus." Journal of Zoology 227, no. 4 (August 1992): 673–84. http://dx.doi.org/10.1111/j.1469-7998.1992.tb04423.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Lancis, J., V. Torres-Company, P. Andrés, and J. Ojeda-Castañeda. "Side-lobe suppression in electro-optic pulse generation." Electronics Letters 43, no. 7 (2007): 414. http://dx.doi.org/10.1049/el:20073672.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

MADDESS, T., R. A. DUBOIS, and M. R. IBBOTSON. "Response Properties and Adaptation of Neurones Sensitive to Image Motion in the Butterfly Papilio Aegeus." Journal of Experimental Biology 161, no. 1 (November 1, 1991): 171–99. http://dx.doi.org/10.1242/jeb.161.1.171.

Full text

Abstract:

Wide-field direction-selective neurones from the optic lobes of the butterfly Papilio aegeus show some properties similar to those displayed by the large neurones of the fly lobula plate. Temporal and spatial frequency threshold tuning curves show that butterfly optic lobe neurones sensitive to different directions of image motion are fed by presynaptic subunits similar to those of the fly. However, unlike fly lobula plate neurones, the butterfly optic lobe neurones show a steep low-spatial-frequency roll-off which persists even at high temporal frequencies. Also exceptional is the temporal resolution of rapid changes in image speed by the butterfly neurones. When the cells are adapted to continuous motion their responses indicate a further increase in temporal resolution. Evidence is provided that in any one state of adaptation the neurones may be thought of as piece-wise linear and, thus, their responses can be predicted by convolution with a velocity kernel measured for that adaptation state. Adaptation to continuous motion results in the cells responding to motion in proportion to the mean motion signal. Motion in the non-preferred direction also appears to adapt the cells. Velocity impulse responses of both butterfly and blowfly neurones were determined with one-dimensional gratings and two-dimensional textured patterns and the results for the two stimuli are shown to be very similar.

APA, Harvard, Vancouver, ISO, and other styles

28

Gold, Katrina S., and Andrea H. Brand. "Optix defines a neuroepithelial compartment in the optic lobe of the Drosophila brain." Neural Development 9, no. 1 (2014): 18. http://dx.doi.org/10.1186/1749-8104-9-18.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Chiang, R. G., and C. G. H. Steel. "Structural organization of neurosecretory cells terminating in the sinus gland of the terrestrial isopod, Oniscus asellus, revealed by paraldehyde fuchsin and cobalt backfilling." Canadian Journal of Zoology 63, no. 3 (March 1, 1985): 543–49. http://dx.doi.org/10.1139/z85-080.

Full text

Abstract:

The morphology of the brain – sinus gland neurosecretory system in the terrestrial isopod, Oniscus asellus, is described with paraldehyde fuchsin and with cobalt backfilling of the sinus gland. Paraldehyde fuchsin stained the A, B, and β cells located medially in the protocerebrum and the γ cells located in the optic lobe. Cobalt applied to the sinus gland delineates an axon tract that extends from the sinus gland medially along the posterior surface of the protocerebrum and descends into the protocerebrum at the level of the central protocerebral neuropile. Cobalt backfilled to the B, β, and γ cells but not to the A cells. One cell group located distally to the most distal optic lobe neuropile filled with cobalt, but was not stained with paraldehyde fuchsin. It is argued that the B and β cells together comprise the equivalent of the decapod "X-organ." Varicosities, which may represent additional storage and (or) release sites for neurosecretion, appear in the axon tract over the region of the optic lobe. Extensive dendritic arborizations of the B and β cells occur along the anterior-medial side of the central protocerebral neuropile. Additional arborizations of these cells occur in the contralateral protocerebral lobe, suggesting a pathway for neural coordination of left and right sinus glands. Further observations on changes in the staining properties of the β and γ cells during the moult cycle suggest the involvement of β cells with moulting and the involvement of γ cells with egg development.

APA, Harvard, Vancouver, ISO, and other styles

30

Kiernan, J. A. "Anatomy of the Temporal Lobe." Epilepsy Research and Treatment 2012 (March 29, 2012): 1–12. http://dx.doi.org/10.1155/2012/176157.

Full text

Abstract:

Only primates have temporal lobes, which are largest in man, accommodating 17% of the cerebral cortex and including areas with auditory, olfactory, vestibular, visual and linguistic functions. The hippocampal formation, on the medial side of the lobe, includes the parahippocampal gyrus, subiculum, hippocampus, dentate gyrus, and associated white matter, notably the fimbria, whose fibres continue into the fornix. The hippocampus is an inrolled gyrus that bulges into the temporal horn of the lateral ventricle. Association fibres connect all parts of the cerebral cortex with the parahippocampal gyrus and subiculum, which in turn project to the dentate gyrus. The largest efferent projection of the subiculum and hippocampus is through the fornix to the hypothalamus. The choroid fissure, alongside the fimbria, separates the temporal lobe from the optic tract, hypothalamus and midbrain. The amygdala comprises several nuclei on the medial aspect of the temporal lobe, mostly anterior the hippocampus and indenting the tip of the temporal horn. The amygdala receives input from the olfactory bulb and from association cortex for other modalities of sensation. Its major projections are to the septal area and prefrontal cortex, mediating emotional responses to sensory stimuli. The temporal lobe contains much subcortical white matter, with such named bundles as the anterior commissure, arcuate fasciculus, inferior longitudinal fasciculus and uncinate fasciculus, and Meyer’s loop of the geniculocalcarine tract. This article also reviews arterial supply, venous drainage, and anatomical relations of the temporal lobe to adjacent intracranial and tympanic structures.

APA, Harvard, Vancouver, ISO, and other styles

31

Guillermin, Oriane, Benjamin Perruchoud, Simon G. Sprecher, and Boris Egger. "Characterization of tailless functions during Drosophila optic lobe formation." Developmental Biology 405, no. 2 (September 2015): 202–13. http://dx.doi.org/10.1016/j.ydbio.2015.06.011.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Caipo, Lorena, M. Constanza González-Ramírez, Pablo Guzmán-Palma, Esteban G. Contreras, Tomás Palominos, Nicolás Fuenzalida-Uribe, Bassem A. Hassan, Jorge M. Campusano, Jimena Sierralta, and Carlos Oliva. "Slit neuronal secretion coordinates optic lobe morphogenesis in Drosophila." Developmental Biology 458, no. 1 (February 2020): 32–42. http://dx.doi.org/10.1016/j.ydbio.2019.10.004.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Yagodin, Sergey, Carlos Collin, Daniel L. Alkon, Norman F. Sheppard, and David B. Sattelle. "Mapping Membrane Potential Transients in Crayfish (Procambarus clarkii) Optic Lobe Neuropils With Voltage-Sensitive Dyes." Journal of Neurophysiology 81, no. 1 (January 1, 1999): 334–44. http://dx.doi.org/10.1152/jn.1999.81.1.334.

Full text

Abstract:

Yagodin, Sergey, Carlos Collin, Daniel L. Alkon, Norman F. Sheppard, Jr., and David B. Sattelle. Mapping membrane potential transients in crayfish ( Procambarus clarkii) optic lobe neuropils with voltage-sensitive dyes. J. Neurophysiol. 81: 334–344, 1999. Voltage-sensitive dyes NK 2761 and RH 155 were employed (in conjunction with a 12 × 12 photodiode array) to study membrane potential transients in optic lobe neuropils in the eye stalk of the crayfish Procambarus clarkii. By this means we investigated a pathway linking deutocerebral projection neurons, via hemiellipsoid body local interneurons, to an unidentified target (most likely neurons processing visual information) in the medulla terminalis. Rapid (10- to 20-ms duration), transient changes in absorption with the characteristics of action potentials were recorded from the optic nerve and the region occupied by deutocerebral projection neurons after stimulation of the olfactory globular tract in the optic nerve and were blocked by 1 μM tetrodotoxin. Action potentials appeared to propagate to the glomerular layer of the hemiellipsoid body where synaptic responses were recorded from a restricted region of the hemiellipsoid body occupied by dendrites of hemiellipsoid body neurons. Action potentials were also recorded from processes of hemiellipsoid body neurons located in the medulla terminalis. Synaptic responses in the hemiellipsoid body and medulla terminalis were eliminated by addition to the saline of 500 μM Cd2+ or 20 mM Co2+, whereas the action potential attributed to branches of deutocerebral projection neurons in the hemiellipsoid body remained unaffected. Action potentials of hemiellipsoid body neurons in the medulla terminalis evoked postsynaptic potentials (50- to 200-ms duration) with an unidentified target in the medulla terminalis. Transient absorption signals were not detected in either the internal or external medulla nor were they recorded from other parts of the optic lobes in response to electrical stimulation of axons of the deutocerebral projection neurons. Functional maps of optical activity, together with electrophysiological and pharmacological findings, suggest that γ-aminobutyric acid affects synaptic transmission in glomeruli of the hemiellipsoid body. Synapses of the olfactory pathway located in the medulla terminalis may act as a “filter,” modifying visual information processing during olfactory stimulation.

APA, Harvard, Vancouver, ISO, and other styles

34

Bacon, J. P., K. S. Thompson, and M. Stern. "Identified octopaminergic neurons provide an arousal mechanism in the locust brain." Journal of Neurophysiology 74, no. 6 (December 1, 1995): 2739–43. http://dx.doi.org/10.1152/jn.1995.74.6.2739.

Full text

Abstract:

1. Habituation is the declining responsiveness of a neural circuit (or behavior) to repetitive stimulation. Dishabituation (or arousal) can be brought about by the sudden presentation of an additional, novel stimulus. A clear example of arousal in the locust is provided by the visual system: the habituated response of the descending contralateral movement detector (DCMD) interneuron to repetitive visual stimuli can be dishabituated by a variety of other visual and tactile stimuli. 2. Application of octopamine to the locust brain and optic lobes dishabituates the DCMD in a manner similar to the effect of visual and tactile stimulation. 3. The locust CNS contains two pairs of octopamine-immunoreactive cells, the protocerebral medulla 4 (PM4) neurons, that could potentially mediate this dishabituation effect; PM4 neurons arborize in the optic lobe, they contain octopamine, and they respond to the same visual and tactile stimuli that dishabituate the DCMD. 4. To investigate whether PM4 activity dishabituates the DCMD, we recorded intracellularly from one of the PM4 neurons while recording extracellularly from the DCMD. When the PM4 neuron is injected with hyperpolarizing current to render it completely inactive, the DCMD exhibits its characteristic habituation to a moving visual stimulus. However, depolarizing the PM4 neuron, to produce action potentials at approximately 20 Hz, significantly increases the number of DCMD action potentials per stimulus. 5. The PM4 neurons may therefore play an important role in dishabituating the DCMD to novel stimuli. This effect is presumably mediated by PM4 neurons releasing endogenous octopamine within the optic lobe.

APA, Harvard, Vancouver, ISO, and other styles

35

Bałys, Monika, and Elżbieta Pyza. "Localization of the clock controlling circadian rhythms in the first neuropile of the optic lobe in the housefly." Journal of Experimental Biology 204, no. 19 (October 1, 2001): 3303–10. http://dx.doi.org/10.1242/jeb.204.19.3303.

Full text

Abstract:

SUMMARYThe visual system of a fly expresses several circadian rhythms that have been detected in the photoreceptors of the compound eye and in the first neuropile, the lamina, of the underlying optic lobe. In the lamina, axons of two classes of interneuron, L1 and L2, exhibit cyclical size changes, swelling by day and shrinking by night. These rhythmic size changes may be generated by circadian oscillators located inside and/or outside the optic lobe. To localize such oscillators, we have examined changes in the axonal cross-sectional areas of L1 and L2 within the lamina of the housefly (Musca domestica) under conditions of 12 h of light and 12 h of darkness (LD12:12), constant darkness (DD) or continuous light (LL) 24 h after the medulla was severed from the rest of the brain. After the lesion, the axon size changes of L1 and L2 were maintained only in LD conditions, but were weaker than in control flies. In DD and LL conditions, they were eliminated. This indicates that circadian rhythms in the lamina of a fly are generated central to the lamina and medulla neuropiles of the optic lobe. Cyclical changes of light and darkness in LD conditions are still able, however, to induce a weak daily rhythm in the axon sizes of L1 and L2.

APA, Harvard, Vancouver, ISO, and other styles

36

Vincze, Orsolya, Csongor I. Vágási, Péter L. Pap, Gergely Osváth, and Anders Pape Møller. "Brain regions associated with visual cues are important for bird migration." Biology Letters 11, no. 11 (November 2015): 20150678. http://dx.doi.org/10.1098/rsbl.2015.0678.

Full text

Abstract:

Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from six continents, we show that the sizes of both the telencephalon and the whole brain decrease, and the relative size of the optic lobe increases, while cerebellum size does not change with increasing migration distance. Body mass, whole brain size, optic lobe size and wing aspect ratio together account for a remarkable 46% of interspecific variation in average migration distance across bird species. These results indicate that visual acuity might be a primary neural adaptation to the ecological challenge of migration.

APA, Harvard, Vancouver, ISO, and other styles

37

Xu, Qian-Hui, Qiu-Yu Li, Kang Yu, Qian-Ming Ge, Wen-Qing Shi, Biao Li, Rong-Bin Liang, Qi Lin, Yu-Qing Zhang, and Yi Shao. "ALTERED BRAIN NETWORK CENTRALITY IN PATIENTS WITH DIABETIC OPTIC NEUROPATHY: A RESTING-STATE FMRI STUDY." Endocrine Practice 26, no. 12 (December 2020): 1399–405. http://dx.doi.org/10.4158/ep-2020-0045.

Full text

Abstract:

Objective: Recent studies have suggested that diabetic optic neuropathy (DON) independently increases the incidence of brain diseases like cerebral infarction and hemorrhage. In this study, voxel-level degree centrality (DC) was used to study potential changes in functional network brain activity in DON patients. Methods: The study included 14 DON patients and 14 healthy controls (HCs) matched by age, sex, and weight. All subjects underwent resting functional magnetic resonance imaging. Receiver operating characteristic curves and Pearson correlation analysis were performed. Results: The DC values of the left frontal mid-orb and right middle frontal gyrus/right frontal sup were significantly lower in DON patients compared to HCs. The DC value of the left temporal lobe was also significantly higher than in HCs. Conclusion: Three different brain regions show DC changes in DON patients, suggesting common optic neuropathy in the context of diabetes and providing new ideas for treating optic nerve disease in patients with long-term diabetes. Abbreviations: AUC = area under the curve; BCVA = best corrected visual acuity; DC = degree centrality; DON = diabetic optic neuropathy; fMRI = functional magnetic resonance imaging; HC = healthy control; LFMO = left frontal mid orb; LTL = left temporal lobe; RFS = right frontal sup; RMFG = right middle frontal gyrus; ROC = receiver operating characteristic

APA, Harvard, Vancouver, ISO, and other styles

38

Paradowski, Bogusław, Edyta Kowalczyk, Justyna Chojdak-Łukasiewicz, Aleksandra Loster-Niewińska, and Monika Służewska-Niedźwiedź. "Three Cases with Visual Hallucinations following Combined Ocular and Occipital Damage." Case Reports in Medicine 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/450725.

Full text

Abstract:

Charles Bonnet syndrome is an underrecognized disease that involves visual hallucinations in visually impaired patients. We present the cases of three patients who experienced complex visual hallucinations following various pathomechanisms. In two cases, diagnosis showed coexistence of occipital lobe damage with ocular damage, while in the third case it showed occipital lobe damage with retrobulbar optic neuritis. Theories of pathogenesis and the neuroanatomical basis of complex visual hallucinations are discussed and supported by literature review.

APA, Harvard, Vancouver, ISO, and other styles

39

Kobayashi, Shiori, Chitoshi Takayama, and Yuzuru Ikeda. "Ontogeny of the brain in oval squid Sepioteuthis lessoniana (Cephalopoda: Loliginidae) during the post-hatching phase." Journal of the Marine Biological Association of the United Kingdom 93, no. 6 (March 26, 2013): 1663–71. http://dx.doi.org/10.1017/s0025315413000088.

Full text

Abstract:

Among invertebrates, cephalopods have one of the most well-organized nervous systems. However, with respect to the ontogeny of the nervous system, the post-embryonic development of the cephalopod brain has only been documented for a few species. Here, we investigated the development of the brain of captive oval squid Sepioteuthis lessoniana during the post-hatching phase. The central part of the brain of the oval squid is divided into four main regions, namely, the supraoesophageal, anterior suboesophageal, middle suboesophageal, and posterior suboesophageal masses, each consisting of several lobes. At various ages in juvenile squid, the total volume of the central part of the brain (except the optic lobe) is significantly correlated with its body size, indicated by mantle length and wet body weight. The vertical lobe, superior frontal lobe, and anterior subesophageal mass drastically increase in relative volume as the squid grows. In contrast, the middle suboesophageal mass and posterior suboesophageal mass do not increase in volume with increasing squid age and body size. The effects of these results have been discussed in relation to the onset of squid behaviours during post-hatching.

APA, Harvard, Vancouver, ISO, and other styles

40

Glassford, William J., and Mark Rebeiz. "Assessing constraints on the path of regulatory sequence evolution." Philosophical Transactions of the Royal Society B: Biological Sciences 368, no. 1632 (December 19, 2013): 20130026. http://dx.doi.org/10.1098/rstb.2013.0026.

Full text

Abstract:

Structural and functional constraints are known to play a major role in restricting the path of evolution of protein activities. However, constraints acting on evolving transcriptional regulatory sequences, e.g. enhancers, are largely unknown. Recently, we elucidated how a novel expression pattern of the Neprilysin-1 ( Nep1 ) gene in the optic lobe of Drosophila santomea evolved via co-option of existing enhancer activities. Drosophila santomea , which has diverged from Drosophila yakuba by approximately 400 000 years has accumulated four fixed mutations that each contribute to the full activity of this enhancer. Recreating and testing the optic lobe enhancer of the ancestor of D. santomea and D. yakuba revealed that the strong D. santomea enhancer activity evolved from a weak ancestral activity. Because each mutation on the path from the D. yakuba/santomea ancestor to modern-day D. santomea contributes to the newly derived optic lobe enhancer activity, we sought here to use this system to study the path of evolution of enhancer sequences. We inferred likely paths of evolution of this enhancer by observing the transcriptional output of all possible intermediate steps between the ancestral D. yakuba/santomea enhancer and the modern D. santomea enhancer. Many possible paths had epistatic and cooperative effects. Furthermore, we found that several paths significantly increased ectopic transcriptional activity or affected existing enhancer activities from which the novel activity was co-opted. We suggest that these attributes highlight constraints that guide the path of evolution of enhancers.

APA, Harvard, Vancouver, ISO, and other styles

41

Nathaniel, Wanmi, Onyeanusi I. Barth, Nzalak J. Oliver, and Aluwong Tanang. "Structural Organization of the Optic Lobe of Grey Breasted Helmeted Guinea Fowl (*Numida meleagris galeata*) at Pre-Hatch Study." Journal of Biology and Life Science 7, no. 2 (August 6, 2016): 26. http://dx.doi.org/10.5296/jbls.v7i2.9850.

Full text

Abstract:

<p class="jbls-body"><span lang="EN-GB">A total of one hundred and seventy-three fertilized eggs were used for morphometry, gross and histological studies. At day 4 of incubation, the mean body weight of the helmeted guinea fowl embryo was 0.6401 ± 0.0211 g. It was at day 10 of incubation that there was an increase in the whole body weight of the embryo to be 0.8650 ± 0.676 g. The whole brain weight indicated relative increased at day 4 as compared to that of the whole body weight. Graphically, there were steady increase in the body, brain and optic lobe weights. Histologically, cells and neurones that make up the optic lobe is probably as a result of the migration of immature cells from the ventricular neuroepithelium. </span></p>

APA, Harvard, Vancouver, ISO, and other styles

42

Pereyra‐Alfonso, S., G. Scicolone, J. L. Ferrán, J. Pecci Saavedra, and V. Flores. "Developmental pattern of plasminogen activator activity in chick optic lobe." International Journal of Developmental Neuroscience 15, no. 6 (October 1997): 805–12. http://dx.doi.org/10.1016/s0736-5748(97)00016-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Ebeling, U., and H. J. Reulen. "Neurosurgical topography of the optic radiation in the temporal lobe." Acta Neurochirurgica 92, no. 1-4 (March 1988): 29–36. http://dx.doi.org/10.1007/bf01401969.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Rind, F. Claire. "Non-directional, movement sensitive neurones of the locust optic lobe." Journal of Comparative Physiology A 161, no. 3 (1987): 477–94. http://dx.doi.org/10.1007/bf00603973.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Giuditta, A., M. Eyman, C. Cefaliello, E. Ferrara, B. B. Kaplan, Z. Scotto Lavina, and R. De Stefano. "Local Synthesis of Presynaptic RNA in Squid Optic Lobe Slices." Biological Bulletin 207, no. 2 (October 2004): 156. http://dx.doi.org/10.1086/bblv207n2p156a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Gewecke, M., K. Kirschfeld, and R. Feiler. "Identification of optic lobe neurons of locusts by video films." Biological Cybernetics 63, no. 6 (October 1990): 411–20. http://dx.doi.org/10.1007/bf00199573.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Barth, Martin, Helmut V. B. Hirsch, Ian A. Meinertzhagen, and Martin Heisenberg. "Experience-Dependent Developmental Plasticity in the Optic Lobe ofDrosophila melanogaster." Journal of Neuroscience 17, no. 4 (February 15, 1997): 1493–504. http://dx.doi.org/10.1523/jneurosci.17-04-01493.1997.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Novakovic, P., D. S. Taylor, and W. F. Hoyt. "Localising patterns of optic nerve hypoplasia--retina to occipital lobe." British Journal of Ophthalmology 72, no. 3 (March 1, 1988): 176–82. http://dx.doi.org/10.1136/bjo.72.3.176.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Rivas, Emilio A., Maria Del Carmen Fernández-Tomé, Juan C. Biancotti, Norma B. Sterin-Spezia, and Sara Fiszer de Plazas. "Ontogenic development of membrane lipids in the chick optic lobe." International Journal of Developmental Neuroscience 14, no. 2 (April 1996): 93–104. http://dx.doi.org/10.1016/0736-5748(95)00089-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Meyer, E. P., C. Matute, P. Streit, and D. R. N�ssel. "Insect optic lobe neurons identifiable with monoclonal antibodies to GABA." Histochemistry 84, no. 3 (1986): 207–16. http://dx.doi.org/10.1007/bf00495784.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Optic lobe'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles